Various systems have been developed to meet the ever increasing demands for power of the modern world. These systems typically use combustible fossil fuels such as natural gas, oil, and coal. Typically, the fossil fuel is burned to generate thermal energy that, in turn, is converted to mechanical energy. While fossil fuel systems are adequate for their intended purpose, these types of systems have two inherent problems. First, the burning of fossil fuels may produce environmentally damaging by-products. Second, the natural supplies of fossil fuels used in these systems are rapidly becoming depleted. Consequently, it has become necessary to develop alternative sources of energy and methods for harnessing these sources.
In order to overcome the inherent problems associated with the use of fossil fuels, various alternative-energy systems have been developed. For example, solar energy systems and systems utilizing wind power are presently in use. Also, bio-fuels made from growing vegetation have also been developed. However, these systems also have certain limitations inherently associated with their use. For example, these systems often require large, expensive, and non-permanent energy-gathering structures such as windmills or solar panels to generate sufficient energy for uses that have modest to high power demands. Hence, given the size requirements of such systems, they are impractical for use in products such as motor vehicles.
Furthermore, other types of systems have been developed that convert heat energy into mechanical energy by circulating a liquefied gas in a closed cycle. In most of these systems, the liquefied gas, during circulation, exchanges heat with heat energy of another substance. Once again, while liquefied gas systems are functional for their intended purpose, these systems are complicated and require specialized equipment in order for the systems to function properly. For example, a known method may include the steps of inserting a liquefied gas in a closed container at a temperature and pressure less than the critical temperature and pressure of the gas. The liquefied gas is heated to the critical temperature and above the critical pressure. The gas is subjected to a heat exchange with another medium thereby heating the gas and cooling the medium. The gas expands to a predetermined pressure, and thereafter, valves open to allow the gas to flow into a high-pressure tank wherein the pressure of the gas is regulated. When the pressure of the gas exceeds a predetermined threshold, a valve on the high-pressure tank is opened and the gas flows to a means such as a turbine that transforms the expansion of the gas into mechanical energy and that reduces the temperature of the gas below the critical temperature. Typically, a portion of the power generated is used to effect the flow of all of the fluids in the system. Thereafter, the gas is liquefied and returned to the closed container. It can be appreciated that the complexity and resulting expense of such a device renders the device close to impractical for many applications.
Accordingly, there is a need in the art for a system and method that overcomes such shortcomings in the art. The present invention addresses these and other needs.